Dual carrier modulation (DCM) is a technology that improves transceiving performance by using frequency diversity.
Frequency diversity means that a transmit end simultaneously transmits a signal by using two transmit frequencies with a relatively large interval, and a receive end simultaneously receives two radio-frequency signals and then combines them. Due to different operating frequencies, correlation between electromagnetic waves is extremely slim, and fading probabilities of all electromagnetic waves are different. Therefore, specially, the frequency diversity effectively resists frequency selective fading, and can improve the transceiving performance. For example, it is assumed that signals to be sent are s1 and s2, signals x1 and x2 are generated after s1 and s2 are combined, and x1=α1s1+β1s2 and x2=α2s1+β2s2. x1 and x2 are simultaneously sent on different frequencies (carriers), and the receive end simultaneously receives the two radio-frequency signals and then combines them, so as to implement the frequency diversity, thereby improving the transceiving performance.
However, with rapid development of wireless communications technologies, people's requirement for improving the transceiving performance is further increased, and transceiving performance of a data transmission method in the prior art cannot meet people's requirement.